That's the beauty of PC gaming: being able to play the way you want.
An alternative to this is the Steam Controller, since you can combine an analog stick or touchpad for movement with a touchpad/gyro for aiming.
You are giving up mouse aiming for it, but some people are more comfortable with a controller, or a controller suits some setups better when you aren't able to use a mouse comfortably.
Unfortunately not all games support simultaneous gamepad + mouse inputs very well, ranging from things like vibration turning off every time you touch the mouse or glyphs constantly switching back & forth, to pauses every time you send an input with one or the other device, or having a gamepad in use locking out mouse inputs entirely.
In recent years, I've noticed a lot more PC gamers that seem to dismiss complaints about games that don't have good input support.
I think it's mostly people that have switched to PC recently and just treat it as if it was a high-end console, using an Xbox controller for everything.
There have been quite a few games recently with poor mouse input handling, or limited/poor handling of mixed inputs.
Not every game will support this, beware. Some games switch between M+KB and controller mode based on which device you press buttons on. You might wanna get one of those keyboards with an analog:
http://ecx.images-amazon.com/images/I/61w9ZwBq3WL._SL1000_.jpg
That's an a 8-way microswitched pad, not an analog stick. Great for quickly selecting weapons or similar functions, but not for movement.
The Logitech G13 has an actual analog stick, but I've heard it's not that comfortable due to its position, and the G13 design laying flat instead of angled.
I do like using a Razer Orbweaver with a mouse though, because it allows me to keep my arms a good distance apart so that they are straight forward, which is a lot more comfortable/ergonomic.
Before that, I would sometimes end up with bad shoulder pain after gaming for a while.
It's why I actually prefer KB&M to a controller most times.